We made it through the night without tripping the breaker. I really think it was the cheap extension cord. You know when the terminal of an electrical cord doesn't have sufficient drag when you plug it in? Making good contact. I'm almost positive it was the arc from the loose phone charger to ext. Cord that caused my problem. Will see though.

I did have a cheaply made extension cord that I was able to trip the breaker once. But wasn't able to repeat the trip. I won't be using it anymore. But in the past the vacuum tripped it also. Will see.... ceiling fan is also running now.

Thanks Dave

The vaccum cleaners are good for tripping the AFCI's espcally with early generation AFCI's. The later models are better.